Baseline and two-year followup data have been collected on a sample of 999 persons who entered treatment for alcohol problems in 1976 and a "control" sample of 500 persons with alcohol abuse problems who did not receive treatment. The Treated group received services from a nationally representative sample of 27 Alcoholism Treatment Facilities. This study will provide descriptive information on the nature of alcoholism treatment programs extant in 1976 and on the baseline characteristics of persons who enter such programs as compared with untreated alcoholics and alcohol abusers. Treatment effectiveness will be assessed using two-year followup data covering patterns and amount of alcohol consumption, alcohol-dependence symptomatology, and social, legal,and interpersonal consequences of alcohol abuse. Medical, psychiatric, psychological, and social correlates of outcome will be described. Detailed data collectd on treatment settings, modalities, amount and duration of services provided to the Treated sample will permit an assessment of the comparative effectiveness of different treatments for alcoholism. Overall rates of treatment effectiveness will also be compared to outcomes in the Untreated sample to determine the incremental benefits of treatment per se over natural remission rates.